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    <title>Document</title>
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    <div class="box">你真是个天才</div>
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        var a = {
            fn: function () {
                $('.box').css('color', 'red')
                return a
            },
            fn1: function () {
                $('.box').addClass('add')
                return a
            },
            fn2: function () {
                $('.box').click(function () {
                    alert('你呀，总能给我整点花样')
                })
            },
        }
        a.fn().fn1().fn2()
    </script>
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